Schematic representation of the compartments of the systemic circulation. The compartments are: ascending and descending aorta with aortic arch, thoracic (with thoracic resistance RTHOR), upper limbs and head, superior and inferior vena cava, renal and hepatic, splanchnic, abdominal and lower limbs (see Systemic Network 6). Atrial and ventricular septa are interdependent and they are modelled using time-varying elastance model. Mitral, tricuspid, pulmonary and aortic valves are modelled using resistance and diode. A model with inverse resistance is used to simulate pulmonary and tricuspid regurgitation.